1. Field of the Invention
The present invention relates to a clock and data recovery circuit, and in particular relates to an all digital clock and data recovery circuit.
2. Description of the Related Art
Demand for large off-chip IO bandwidth requires many serial links on a chip. The serial links need to be low-powered, compatible to different technologies, and operate reliably in noisy environments. One example of a serial link component is a clock and data recovery (CDR) circuit.
While analog CDR circuits have good performance, it takes time for analog CDR circuits to be ported to different technology. For a digital CDR circuit, it is insusceptible to leakage, does not need the passive elements, and prohibits quick production-level testing.